Reversible combustion engine



Oct. 15, 1929.

M. ROTTER REVERSIBLE COMBUS TION ENGINE 2 Sheets-Sheet 1 Filed Aug. 28. 1926 afiead "WENTUR 5 ATTORNEYS air startinp- Oct. 15, 1929. M. ROTTER REVERSIBLE COMBUSTIQN ENGINE Filed Aug. 28. 1926 2 Sheets-Sheet 2 ORNEYs Patented Got. 15, 1929 UNITED STATES PATENT OFFICE MAX ROTTIER, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO BUSGH-SULZER BROS.-

DIESEL ENGINE COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION OF MISSOURI REVERSIBLE COMBUSTION ENGINE Application filed August 28, 1926. Serial No. 132,111.

In reversing internal combustion engines dangerously high pressures may be developed in the cylinders through the premature readmission of the fuel. The object of my invention is to prevent or guard against the operation of the engine in such a Way as to develop such dangerous pressures. The invention relates particularly to air-started marine engines of the Diesel type.

The accompanying drawings illustrate two forms of the invention. Fig. 1 shows generally the invention applied to a ship, and specifically a form of the invention working directly on the engine operating handle. Figs. 2 and 3 are enlarged details of mechanism of Fig. 1 showing the parts in different positions. Fig. d is a diagrammatic elevation, partly in section, of a form of the invention working on the engine fuel pump, the parts being shown in engine running position. Fig. 5 is a perspective of a-detail, of Fig. 4. Fig. 6 is a plan view of a portion of the mechanism of Fig. 4. Fig. 7 is an elevation-of the mechanism adjacent the control shaft of Fig. 4, looking at right angles to the latter figure. Fig. 8 is a reproduction of a portion of Fig. 4: to show the parts in neutral or stop position.

Referring first to the apparatus illustrated in Figs. 1 to 3: In the vessel partly outlined at 1, the multicylinder propelling engine 2 may be assumed to be of any suitable design of the general type referred to; it drives the propeller 3 through the shaft 4 in the usual. way. Much of the valve gearing and various of the usual engine auxiliaries and accessories are omitted from the drawing for clarity. The engine control mechanism or device whereby the operator controls or restrains the supply of fuel to the engine at will, and

the reversing mechanism, are represented solely by the operating and reversing handles 7 and 8 thereof. It will be understood that the control mechanism or device includes suitable gearing connecting the operating handle 7 to the fuel supply system of the engine so that by moving the handle 7 the operator restrains the supply offuel or permits fuel to pass freely, or more freely, to the engine cylinders as required; and likewise gearing handles are shown as levers in Figs. 1 and 2,

the operating lever 7 having the customary three positions of air starting, stop and running, arranged in that order, and the reversing lever the usual ahead and astern positions. The operating lever 7' is both a part of the starting air mechanism of the engine and a part of the fuel supplying and restraining mechanism; in the air starting position of the operating lever, compressed air alone is admitted to start the engine; while in the normal operating or running position, the compressed starting air is cut off and fuel is supplied to the cylinders in controlled amount to continue the operation, and in stop neither fuel nor compressed air is supplied and if the lever is left in this position the engine will come to rest. The reversing lever 8 so adjusts the valve gearing that, ac-

cording'to its position, the cam shaft aetuates the respective valves at the proper times to rotate the crank shaft in either the forward or the backward direction. The control levers may be assumed to be interlocked in any suitable or usual manner so as to prevent the actuation of the reversing lever except when the operating lever is in its stop position, and also to prevent the movement of the operating lever to either side of stop except when thereversing lever is in its ahead or astern position, this being according to customary and usual practice. After the reversing lever has been thrown, the operating le ver may then be moved from stop to air starting and compressed air thereby admitted either to assist in stopping the engine or to propel it. \Vhen making a reversal, how ever, the operator, either through carelessness or because the enclosed construction prevents externally threaded.

inspection of the rotating engine parts, may return the operating handle to running while the machine is still. rotating in the original direction; that is to say, after he has thrown the reversing lever, but before the engine has'stopped, he may readmit the fuel. This is particularly likely to happen on ship board where the force of the water on the propeller as the ship continues to dri't in the original direction, is sufficient to cause the engine shaft to continue to rotate in the original direction even against the pressure of the starting air. If under such circumstances, the operating lever is moved to running, ignition of the fuel takes place during the inward strokes of the pistons and dangerous pressures develop in the cylinders. By the present invention the e must come suhstantially to a full stop before fuel can be readmitted.

As shown, the operating lever i" is arranger to move between the fixed bars or guides 13 and 14k and these latter are perforated for the reception of two stop pins 15 and 16 that project from a sliding frame 17 and are adaped to be extended alternately into the path of the operating lever according as the frame is moved to the right or left and so form an obstruction to said lever located in termediate its running and stop p sitions see Fig. In the neutral or n "deposition of the frame 17 neither pin ohm" ts the operating lever which may then pass between them (Fig. 2). The legs 19 and 20 of the sliding frame 17 are engaged in circumferential end grooves in a sleeve 21 that is mounted to slide on the cam shaft 9 and is The nut 22 on this sleeve screw carries a stud 23 engaged with the forked end of a lever'2 l pivoted to a stationary part of the engine and connected through the link 25 to the reversing lever 8;

through this connection the shifting of the reversing lever to its astern setting slides the sleeve screw on the cam shaft and there 3y moves the frame 17 to the right i 3 This projects stop pin 16 into the path of operating lever 7 between its stop and ri. 1- ning positions as indicated. Similarly, returning the reversing; lever to ahead moves the sleeve and frame to the left and projects the opposite stop finger 15 into the path of the operating lever. The opposite ends of the screw sleeve are provided also wi i onpositcly directed ratchet clutch teeth, each end being; adapted to engage and be driven by complementary atchet clutch teeth formed on the adjacent clutch member 31 or 32, which latter are splined to the cam shaft and urged toward the screw sleeve hy helical springs 35 and 36 and against the fixed stop collars 3'? and 38. These collars are so lo cated that the sleeve screw when oecupyino a middle position is out of engagement with both said sliding clutch members. When the connections 24; and 25 with the reversing lever have move l the screw sleeve into engagement with either clutch member however, the sleeve screw will be rotated thereby provided the rotation of the cam shaft conforms to the facing of the ratchet teeth. A guide 43 iii-zed to a stationary part of the engine and projecting into a slot in the nut 22 parallel with the shaft axis, holds the nut against rotation while permitting to slide endwise.

The operation of the apparatus of Figs. 1 to is as follows: In normal running, whether aiiead or astern, the sleeve-screw and atop pins occupy the neutral position of Fig. The operating; lever is therefore free to is moved back and forth as required to con rol of the engine for one direction of running. To reverse the engine, assi: g it to running ahead or with the cam shaft be rotating in the direction of the arrow 42 and in which case the nut 22 will be on the left hand end of the sleeve screw as shown in Fl 2. the operating lever 7 is first moved to stop, thus cutting off the fuel' the reverse inn; lever 8 is then shifted to reverse or astcrn. This movement slides the sleeve screw 21 into contact with the clutch 31 at the to running or fuel-supplying position. So long as forward drift of the ship keeps the engine sl ..;t turning; in the forward direction, and correspondingly the cam shaft continues to turn in the direction of the arrow 4-2, the stop pin 16 remains held in this blocking; out position, the ratchet clutch teeth 31 simply riding over the complementary teeth on the sleeve with no other effect than the compression. of the spring 35. The operating' handle 7 can now he moved to air starting position and the engine thereby started in reverse and at any time the operating l andle can he moved back far as the stop position, but the stop pin 16 prevents move-- ment beyone this point to the fuel-supply running position so long as the sleeve screw remains contact with the clutch 31. When 'mat v the compressed air has reve sed the direction of the cam shaft rotation however, and thereby caused the cam shaft to retate in the direction of the arrow ll 3) the teeth of the clutc 81 will lock vith the teeth of the sleeve screw (Fig. turn the latter in the nut 22, and thus cause the sleeve screw 21 to travel to the left until its teeth clear the teeth 31. At this pointthe sleeve screw will have reached its neutral position of Fig. 2 again and the stop pin 16 be withd awn from the path of he operating lever. Fuel. can now he adn'iitted and the operation of the engine on fuel begun. The nut 22 is now at the right hand end of the sleeve screw of course; hence it will be apparent that to rethe engine again, that is to say, to cause it to drive ahead again, in the direction of the arrow 12, the opposite shifting of the re vcrsing lever 8 to ahead (which can be done only when the operating lever 7 is in stop position) will move the sleeve screw 21 to the left into en agement with clutch 32 and hold the stop pin 15 back of the operating lever until the rotation of the cam shaft 9 rotates in the ahead direction of arrow 12 and then causes clutch 32 to return the sleeve screw and frame to neutral as before and all the parts to the positions of Fig. 2.

The amount of turning necessary to accomplish this result in each instance, that is to say, the number of revolutions the engine must make in the new direction in order to release the operating lever, is predetermined by the pitch of the threads on the sleeve screw or by the depth of the ratchet teeth. Obviously the clutches and sleeve screw may be applied to any other shaft that is rotated with the engine crank shaft in reversing, rather than to the cam shaft as shown, and indeed the releasing function of these parts may be accomplished by other mechanisms under the control of driven parts of the engine. In no way does the mechanism described interfere with maneuvering, that is to say, the engine may be stopped any stage of reversing, and at any stage prior to actual reversing the reversing operation may be discontinued and the engine operation resumed in its original direction as though the mechanism of the invention were not present.

It will now be understood that the principle of my invention resides in delaying the re-.

turn to fuel operation, in reversing, until the engine is quite or substantially stopped, and preferably until after the rotation of the engine has been started again in the new direc tion. The mechanism described requires an invariable sequence in reversing; the preferred and usual coincident interlocking of the operating handle and reversing handle assures the discontinuance of the fuel supply prior to the actuation of the lock and thereby eliminates possible careless locking of the fuel mechanism in fuel supplying position, and after fuel operation has been stopped it can be resumed again (assuming the reversing is persisted in) only after the engine has actually begun its rotations in the reverse direction.

Referring now to Figs. 1 to 8 which illustrate apparatus embodying the same principles, but an apparatus in which such control is exercised on the fuel supply system thatno fuel is delivered to the engine cylinders until after the reversal of the engine is completed. This leaves the operator free to move the operating handle to any position at any time, except of'course as it may be interlocked with the reversing mechanism. The operating handle is again designated 7 and the reversing handle (in this case a hand wheel or attached to a hand wheel) is desig- .53 and the deliverypipes' (leading the fuel to the engine injection valves), at 54. The suction valves 51 are arranged to'be opened by a reciprocating member 55 which strikes bell crank levers 56 (the lower end of only one of these is shown) and thereby depresses the upper arms 57 of the bell cranks which carry cross members 58 having'pins 59 to depress the suction valves as will be understood. The bell crank levers 5657 turn on eccentrics 60 attached to the shafts 61, so that the length of the valve-open periods can be changed by rocking the shafts 61; thereby the amount of fuel supplied in the engine can be controlled in the manner described in the Hawkes patent. Control can be exercised from a number of stations substantially in the manners described in the patent, among others by the operating handle 7 which is fixed to the control shaft 64. For the purposes of this description, the crank arms 65 and 66 may be regarded as fixed to the shafts 61 so that as the crank 65 is turned counter clockwise 4) and crank 66 clockwise the suction valves 51 are held open for progressively longer periods and in their limit positions do not close at all; in the limit positions of the cranks 65 and 66 therefore the reciprocation of the plunger 52 simply causes the fuel to surge back and forth around the suction valves and none is delivered to the engine cylinders. Links 67 and 68 connect the cranks 65 and 66 respectively to the operating handle 7 in the manner later described. While I have illustrated the Hawkes patented type of fuel pump it will be understood that my invention is not limited to this type of pump. The point I wish principally to illustrate is a fuel supplying mechanism which ceases to deliver fuel to the engine as the links 67 and 68, for example, dictate; action on the suc tion valves of the fuel pump so that these valves are held open throughout the entire stroke of the pump plungers when the links 67 and 68 or other appropriate mechanism is called into action, is a preferred manner of doing this.

As in the construction of Figs. 1 to 3, I also use here an externally threaded or screw sleeve 69 mounted loosely on the engine cam shaft 9 or on some other shaft connected to the engine crank shaft to rotate ahead or astern in accordance with the rotation of the engine crank shaft. Also as before, this screw sleeve is provided at its two ends with oppositely facing clutch teeth to engage with correspondingly facing clutch teeth on clutch members 70 and 71 which are keyed to rotate with the shaft 9 by means of the pins 72 extending into axially aligned slots in the clutch limited thereto except as appears hereinafter in the claims.

I claim:

1. In an internal combustion engine including engine reversing mechanism and a device for controlling the supply of fuel to the engine, means interlocking said device and the engine reversing mechanism to prevent the actuation of the reversing mechanism to reverse position until the said device is actuated to restrain the supply of fuel to the engine, a locking member to lock said device in a position in which the supply of fuel to the engine is restrained, connecting means between said locking member and said reversing mechanism through which the locking member is moved to locking position on setting said reversing mechanism for reversal, and connecting means between the crank shaft and said locking member to cause the movement of said locking member to unlocked position.

2. In an internal combustion engine, the combination of the engine crank shaft, engine reversing mechanism, a device for restraining the supply of fuel to the engine, said device being interlocked with the engine reversing mechanism to prevent actuation of the reversing mechanism to engine reversing position prior to the imposing of restraint on the supply of fuel, and means driven by the engine crank shaft after reversal to release restraint on the supply of fuel to the engine.

3. In an internal combustion engine having a reversing mechanism, a device to prevent the supply of fuel to the engine, said device being interlocked with the reversing mechanism to prevent the supply of fuel to the engine after the reversing mechanism has been actuated to engine reversing position, a shaft rotating with the engine crank shaft, and a threaded member driven by said shaft in coaction with its threads after reversal and controlling said de ice to permit the supply of fuel.

4:- In an internal combustion engine including en 'ine reversing mechanism, a device for restraining the supply of fuel to the engine, and connection means from said device to the reversing mechanism and the engine crank shaft through which the re versing mechanism acts to impose restraint on the supply of fuel to the engine and the engine crank shaft acts to release restraint on the supply of fuel to the engine.

5. In an internal combustion engine including engine reversing mechanism and a device for controlling the supply of fuel to the engine, a locking member to lock said device in a position in which the supply of fuel to the engine is restrained, connecting means between said locking member and said reversing mechanism through which the looking member is moved to locking position on setting said reversing mechanism for reversal, and connecting means between 1 the crank combination of the engine crank shaft, engine shaft and said locking member to cause the reversing mechanism, a device actuated by the reversing mechanism to maintain restraint on the supply of fuel to the engine after the reversing mechanism has been actuated to engine-reversing position, and means driven by the engine crank shaft after reversal controlling the release of restraint on the supply of fuel to the engine.

7. In an internal combustion engine, a device for restraining the supply of fuel to the engine, and a connection between said device and the engine crank shaft through which the crank shaft acts on said device to relieve restraint on the supply of fuel to the engine.

8. In an internal combustion engine, a device to prevent the supply of fuel to the engine, a shaft rotating with the engine crank shaft, and a threaded member driven by said shaft in coaction with its threads to actuate said device.

9. In an internal combustion engine, the combination of means to prevent the supply of fuel to the engine, a shaft rotating with the engine crank shaft, a threaded sleeve slidable axially on said shaft and arranged in its two extreme positions to be rotated by the shaft, said sleeve being so related to said means as to prevent the supply of fuel to the engine when in its two extreme positions and permit the-supply of fuel when in its midposition, a member engaging with the threads of the sleeve so that the sleeve is moved axially as it is rotated, and a reversing mechanism for the engine interlocked with the sliding of the sleeve axially.

10. In an internal combustion engine, the combination of means to prevent the supply of fuel to the engine, a shaft rotating with the engine crank shaft, an externally threaded sleeve slidable on said shaft and having teeth facing in opposite directions on its two ends,

said sleeve being so related to said means as V to prevent the supply of fuel to the engine when in its two extreme positions and permit the supply of fuel when in its midposition, clutch members rotating with the shaft at the two ends of the sleeve, saidclutch members being movable away from the sleeve and having corresponding oppositely faced teeth to engage the teeth on the sleeve to rotate the sleeve when in either of its two extreme positions, a nut on the sleeve, and engine reversing mechanism connected to the nut to slide the sleeve axially to its extreme positions as the reversing mechanism is actuated to reverse the engine.

11. In an internal combustion engine, the combination of its reversing gear, a device controlling the supply of fuel and interlocked with the reversing gear, coacting nut and threaded members, one of said members being held'against rotation, and means connecting the other of said members to the engine crank shaft to turn With thelatter in reverse, one of said members being movable axially by such turning to cause said fuel controlling device to permit the supply or fuel.

In testimony whereof, I have signed this specification.

MAX BUTTER. 

